Radio frequency integrated circuit having frequency dependent noise mitigation with spectrum spreading

ABSTRACT

A radio frequency integrated circuit (RFIC) includes a low noise amplifier that amplifies an inbound radio frequency (RF) signal to produce an amplified RF signal. A down conversion module converts the amplified RF signal to a down converted signal based on a local oscillation. An analog to digital conversion (ADC) module coupled to convert the down converted signal into a digital signal. A baseband processing module converts the digital signal into inbound data, wherein at least one function of the baseband processing module is clocked by a plurality of baseband clock signals A clock module produces the plurality of baseband clock signals, wherein the clock module detects an interference condition when frequency dependent noise components associated with at least one of the plurality of baseband clock signals are inside a frequency band associated with the inbound RF signal, and spreads the spectrum of the at least one of the plurality of baseband clock signals when the interference condition is detected.

CROSS REFERENCE TO RELATED PATENTS

The present application is a continuation-in-part of pending U.S. patentapplication Ser. No. 11/494,147, entitled, INTEGRATED CIRCUIT HAVINGFREQUENCY DEPENDENT NOISE AVOIDANCE, filed on Jul. 26, 2006.

In addition, the present application is related to U.S. patentapplication Ser. No. ______, entitled, RADIO FREQUENCY INTEGRATEDCIRCUIT HAVING FREQUENCY DEPENDENT NOISE AVOIDANCE, filed concurrentlyherewith.

BACKGROUND OF THE INVENTION

1. Technical Field of the Invention

This invention relates generally to integrated circuits and moreparticularly to noise control within integrated circuits, such as RFintegrated circuits.

2. Description of Related Art

As is known, integrated circuits are used in a wide variety of productsincluding, but certainly not limited to, portable electronic devices,computers, computer networking equipment, home entertainment, automotivecontrols and features, and home appliances. As is also known, integratedcircuits include a plurality of circuits in a very small space toperform one or more fixed or programmable functions.

Many integrated circuits include circuitry that is sensitive to noiseand circuitry that produces noise. For example, a radio frequencyintegrated circuit (RFIC), which may be used in a cellular telephone,wireless local area network (WLAN) interface, broadcast radio receiver,two-way radio, etc., includes a low noise amplifier (LNA) that issusceptible to adverse performance due to noise and also includes ananalog to digital converter and other digital circuitry that producenoise. To prevent the noise from adversely affecting the noise sensitivecircuits (e.g., the LNA) many noise reduction concepts have beendeveloped.

The simplest noise reduction concept is to put noise sensitive circuitson a different IC die than noise producing circuits. While this solvesthe noise sensitivity issue, it does not provide the reduction in formfactor that many products and/or devices are required to have. Anothertechnique is to have the noise sensitive circuits on separate powersupply lines (e.g., positive rail, negative rail, and/or return) andconnected together off-chip. Other techniques include layout management,shielding, etc.

While each of these techniques provides varying levels of noisemanagement, their effectiveness is reduced as the fabrication process ofintegrated circuit shrink and/or as more circuits are placed on the sameintegrated circuit die. Therefore, a need exists for an integratedcircuit that reduces the adverse affects of noise.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed to apparatus and methods of operationthat are further described in the following Brief Description of theDrawings, the Detailed Description of the Invention, and the claims.Other features and advantages of the present invention will becomeapparent from the following detailed description of the invention madewith reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

FIG. 1 is a schematic block diagram of an embodiment of an integratedcircuit in accordance with the present invention;

FIG. 2 is a frequency diagram of clock adjusting in accordance with thepresent invention;

FIG. 3 is a schematic block diagram of another embodiment of anintegrated circuit in accordance with the present invention;

FIG. 4 is a frequency diagram of clock adjusting in accordance with thepresent invention;

FIG. 5 is a schematic block diagram of an embodiment of a radiofrequency integrated circuit in accordance with the present invention;

FIG. 6 is a schematic block diagram of an embodiment of a downconversion module in accordance with the present invention;

FIG. 7 is a schematic block diagram of an embodiment of a clock modulein accordance with the present invention;

FIG. 8 is a schematic block diagram of another embodiment of a clockmodule in accordance with the present invention.

FIG. 9 is a schematic block diagram of an embodiment of a radiofrequency integrated circuit in accordance with the present invention;

FIG. 10 is a schematic block diagram of an embodiment of a clock modulein accordance with the present invention;

FIG. 11 is a schematic block diagram of another embodiment of a clockmodule in accordance with the present invention.

FIG. 12 is a schematic block diagram of an embodiment of a clock sourcein accordance with the present invention;

FIG. 13 is a schematic block diagram of another embodiment of a clocksource in accordance with the present invention.

FIG. 14 is a schematic block diagram of another embodiment of a clockmodule in accordance with the present invention.

FIG. 15 is a frequency diagram of clock spectrum adjusting in accordancewith the present invention;

FIG. 16 is a flow chart of a method in accordance with the presentinvention;

FIG. 17 is a flow chart of a method in accordance with the presentinvention;

FIG. 18 is a flow chart of a method in accordance with the presentinvention;

FIG. 19 is a flow chart of a method in accordance with the presentinvention;

FIG. 20 is a flow chart of a method in accordance with the presentinvention; and

FIG. 21 is a flow chart of a method in accordance with the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a schematic block diagram of an embodiment of an integratedcircuit (IC) 10 that includes a noisy circuit 12, a rate dependentcircuit 14, a noise susceptible circuit 16, a clock module 18, and arate adapting module 20. The circuits 12, 14, and 16 may be any type ofanalog and/or digital circuits that can be implemented on an integratedcircuit including, but not limited to, amplifiers, memory,microprocessors, microcontrollers, baseband processing module, digitalsignal processors, digital logic circuitry, multipliers, adders,arithmetic logic units, analog to digital converters, digital to analogconverters, sensors, impedance matching circuits, input-output circuits,state machines, mixers, and control logic.

The clock module 18, which may be a fractional-N frequency synthesizer,a direct digital frequency synthesizer, a phase locked loop, and/or anycircuit that generates a sinusoidal or square wave repetitive signal ata desired rate, generates a clock signal 22. The noisy circuit 12 isclocked based on the clock signal 22 and when operating causes frequencydependent noise. For instance, the noisy circuit 12 may be clockeddirectly from the clock signal 22, a multiple of the clock signal 22, ora fraction of the clock 22 and causes frequency dependent noise 24 to bepresent in the IC 10. The frequency dependent noise 24, which may beharmonic signal components, spurs, and/or digital noise, may appear onthe substrate of the IC 10, on the positive supply voltage rail, onnegative supply voltage rail, a voltage return rail and/or be introducedinto a circuit or other module via electromagnetic cross-coupling noiseintroduced on control lines or other inputs, etc.

The noise susceptible circuit 16 is susceptible to adverse performancewhen the frequency dependent noise 24 has a component within a givenfrequency range. The given frequency range may be associated with thebandwidth of signals processed by the noise susceptible circuit 16and/or may be a range of operating frequencies of the noise susceptiblecircuit 16. To minimize the adverse performance of the noise susceptiblecircuit 16 due to the frequency dependent noise 24, the rate of theclock signal 22 is set such that components of the frequency dependentnoise 24 associated with the clock signal 22 are outside the givenfrequency range.

The rate dependent circuit 14 requires a specific clock rate (which maybe at a different rate than that of the clock signal 22) to perform oneor more of its functions is clocked based on an operation dependentclock signal 26. The rate adapting module 20, which may be afractional-N frequency synthesizer, a direct digital frequencysynthesizer, a phase locked loop, and/or digital logic circuitry (e.g.,a digital delay line to produce a plurality of delayed clock signalsfrom the clock signal 22, a plurality of inverters to produce aplurality of inverted delayed clock signals, a multiplexer to select oneof the plurality of delayed or inverted delayed clock signals to clock aD flip-flop), is coupled to produce the operation dependent clock signal26 from the clock signal 22.

In one embodiment, the rate adapting module 20 establishes theoperational dependent clock signal 26 by establishing an adjustmentfactor based on the rate dependency of the rate dependent circuit 14 andthe clock signal 22. For example, if the rate dependency of the ratedependent circuit 14 is 100 MHz and the clock signal 22 has a rate of105 MHz, the adjustment factor is 100/105. Having established theadjustment factor, the rate adapting module 20 adjusts the rate of theclock signal 22 based on the adjustment factor to produce the operationdependent clock signal 26.

In one embodiment, the clock module 18 determines whether components ofthe frequency dependent noise 24 are within the given frequency rangefor an initial rate of the clock signal 22. The initial rate of theclock signal 22 may be set at desired rate for the rate dependentcircuit 14, a multiple thereof, and/or a fraction thereof. Note that thedetermining may be done by calculating frequency of the components ofthe frequency dependent noise 24 based on the initial clock rate.Alternatively, the IC 10 may be operated in a test mode at the initialrate of the clock signal 22 and monitoring performance of the noisesusceptible circuit 16. If noise susceptible circuit 16 experiencesminimal adverse affects due to the frequency dependent noise 24 then itcan be assumed that there are no significant components of the frequencydependent noise in the given frequency range.

When the frequency dependent noise components are within the givenfrequency range, the clock module 18 adjusts the rate of the clocksignal 22 such that the frequency dependent noise components associatedwith the clock signal 22 are outside the given frequency range. In oneembodiment, the clock module 18 adjusts the rate of the clock signal 22by calculation. For instance, if the given frequency range is from 960MHz to 1040 MHz, and the initial rate of the clock is 100 MHz, the tenthharmonic of the clock signal 22 is 1000 MHz and is within the givenfrequency range. As such, the clock module 18 determines that a clockrate of 105 MHz produces a ninth harmonic at 945 MHz and a tenthharmonic at 1050 MHz, both of which are outside of the given frequencyrange. Alternatively, the clock module 18 may use a clock rate of 95MHz, which has a tenth harmonic at 950 MHz and an eleventh harmonic at1045 MHz, both of which are outside the given frequency range.

In another embodiment, the clock module 18 may incrementally increase ordecrease the rate of the clock signal 22 during a test mode, where theIC 10 monitors for adverse performance of the noise susceptible circuit14 due to the frequency dependent noise 24. When an acceptable level ofperformance is obtained for a given rate of the clock signal, it is usedfor the clock signal 22. Note that in any of the embodiments of FIGS.1-8, an interpolating and/or anti-aliasing filter may be requiredbetween the noisy circuit and the rate dependent circuit if the noisycircuit and rate dependent circuit are coupled in a series fashion.

FIG. 2 is a frequency diagram of an example of clock adjusting withinthe IC 10 of FIG. 1. In this illustration, the fundamental frequency ofthe operation dependent clock signal 26 includes harmonics 42 that areillustrated using dashed lines. If this rate were used for the clocksignal 22, then there would be a harmonic within the given frequencyrange 40, which might adversely affect the performance of the noisesusceptible circuit. As such, the rate of the clock signal 22 isadjusted such that the fundamental frequency of the clock signal 22 isgreater than or less than (shown as greater than) the rate of theoperation dependent clock signal 26. By adjusting the rate of the clocksignal 22, its harmonic components are also adjusted and can be adjustedto be outside the given frequency range 40. However, the rate dependentcircuit 14 requires a clock based on the operation dependent clocksignal 25, which is derived from the clock signal 22 by the rateadapting module.

FIG. 3 is a schematic block diagram of another embodiment of anintegrated circuit (IC) 50 that includes a noisy circuit 52, a circuit54, a noise susceptible circuit 56, a clock module 58, and a rateadapting module 60. The circuits 52, 54, and 56 may be any type ofanalog and/or digital circuits that can be implemented on an integratedcircuit including, but not limited to, amplifiers, memory,microprocessors, microcontrollers, digital signal processors, basebandprocessing module, digital logic circuitry, multipliers, adders,arithmetic logic units, analog to digital converters, digital to analogconverters, sensors, impedance matching circuits, input-output circuits,state machines, mixers, and control logic.

The clock module 58, which may be a fractional-N frequency synthesizer,a direct digital frequency synthesizer, a phase locked loop, and/or anycircuit that generates a sinusoidal or square wave repetitive signal ata desired rate, generates a clock signal 62. The clock module 58provides the clock signal 62, a multiple thereof, or a fraction thereofto the circuit 54, which requires a specific clock rate to perform oneor more of its functions. Accordingly, the clock module 58 sets the rateof the clock signal 62 to provide the desired clock for the circuit 54.However, if the clock signal 62 were used to clock the noisy circuit 52,frequency dependent noise 64 would be within a given frequency range ofthe noise susceptible circuit 56.

The noise susceptible circuit 56 is susceptible to adverse performancewhen the frequency dependent noise 64 has a component within a givenfrequency range. The given frequency range may be associated with thebandwidth of signals processed by the noise susceptible circuit 56and/or may be a range of operating frequencies of the noise susceptiblecircuit 56. To minimize the adverse performance of the noise susceptiblecircuit 56 due to the frequency dependent noise 64, the rate of theadjusted clock signal 66 is set such that frequency dependent noise 64associated with the adjusted clock signal 66 is outside the givenfrequency range.

To move the frequency dependent noise 64 outside of the given frequencyrange, the rate adapting module 60, which may be a fractional-Nfrequency synthesizer, a direct digital frequency synthesizer, a phaselocked loop, and/or digital logic circuitry (e.g., a digital delay lineto produce a plurality of delayed clock signals from the clock signal62, a plurality of inverters to produce a plurality of inverted delayedclock signals, a multiplexer to select one of the plurality of delayedor inverted delayed clock signals to clock a D flip-flop), is coupled toproduce the adjusted clock signal 66 from the clock signal 62. The rateadapting module 60 provides the adjusted clock signal to the noisycircuit 52.

The noisy circuit 52 is clocked based on the adjusted clock signal 66and when operating causes frequency dependent noise 64. For instance,the noisy circuit 52 may be clocked directly from the adjusted clocksignal 66, a multiple of the adjusted clock signal 66, or a fraction ofthe adjusted clock signal 66 and causes frequency dependent noise 64 tobe present in the IC 10. The frequency dependent noise 64, which may beharmonic signal components, spurs, and/or digital noise, may appear onthe substrate of the IC 50, on the positive supply voltage rail, onnegative supply voltage rail, a voltage return rail and/or be introducedinto a circuit or other module via electromagnetic cross-coupling noiseintroduced on control lines or other inputs, etc.

In one embodiment, the rate adapting module 60 establishes the adjustedclock signal 66 by establishing an adjustment factor based on the givenfrequency range and the clock signal 62. For example, if the givenfrequency range is 960 MHz to 1040 MHz and the rate of the clock signal62 is 100 MHz, then the clock signal has a tenth harmonic at 1000 MHz.The rate adapting module 60 may then determine the adjustment factor as960/1000 or 1040/1000. Having established the adjustment factor, therate adapting module 60 adjusts the rate of the clock signal 62 based onthe adjustment factor to produce the adjusted clock signal 66.

In one embodiment, the rate adapting module 60 determines whethercomponents of the frequency dependent noise 64 are within the givenfrequency range for the clock signal 62. Note that the determining maybe done by calculating the frequency of the components of the frequencydependent noise 64 based on the clock rate. Alternatively, the IC 50 maybe operated in a test mode at the rate of the clock signal 62 andmonitoring performance of the noise susceptible circuit 56. If noisesusceptible circuit 56 experiences minimal adverse affects due to thefrequency dependent noise 64 then it can be assumed that there are nosignificant components of the frequency dependent noise in the givenfrequency range.

When the frequency dependent noise components are within the givenfrequency range, the rate adapting module 60 adjusts the rate of theclock signal 62 such that the frequency dependent noise componentsassociated with the adjusted clock signal 66 are outside the givenfrequency range. In one embodiment, the rate adapting module 60 adjuststhe rate of the clock signal 62 by calculation. For instance, if thegiven frequency range is from 960 MHz to 1040 MHz, and the rate of theclock is 100 MHz, the tenth harmonic of the clock signal 62 is 1000 MHzand is within the given frequency range. As such, the rate adaptingmodule 60 determines that a clock rate of 105 MHz produces a ninthharmonic at 945 MHz and a tenth harmonic at 1050 MHz, both of which areoutside of the given frequency range. Alternatively, the rate adaptingmodule 60 may use a clock rate of 95 MHz, which has a tenth harmonic at950 MHz and an eleventh harmonic at 1045 MHz, both of which are outsidethe given frequency range.

In another embodiment, the rate adapting module 60 may incrementallyincrease or decrease the rate of the adjusted clock signal 66 during atest mode, where the IC 50 monitors for adverse performance of the noisesusceptible circuit 54 due to the frequency dependent noise 64. When anacceptable level of performance is obtained for a given rate of theadjusted clock signal, it is used for the adjusted clock signal 66.

FIG. 4 is a frequency diagram of an example of clock adjusting withinthe IC 50 of FIG. 3. In this illustration, the fundamental frequency ofthe clock signal 62 includes harmonics 42 that are illustrated usingdashed lines. If this rate were used to clock the noisy circuit 52, thenthere would be a harmonic within the given frequency range 70, whichmight adversely affect the performance of the noise susceptible circuit56. As such, the rate of the adjusted clock signal 66 is establishedsuch that its fundamental frequency is greater than or less than (shownas less than) the rate of the clock signal 62. By adjusting the rate ofthe adjusted clock signal 66, its harmonic components are also adjustedand can be adjusted to be outside the given frequency range 70.

FIG. 5 is a schematic block diagram of an embodiment of a radiofrequency integrated circuit (RFIC) 80 that includes a low noiseamplifier 82, a down conversion module 84, an analog to digitalconverter module 86, a baseband processing module 88, and a clock module90. The baseband processing module 88 executes digital receiverfunctions that include, but are not limited to, digital intermediatefrequency to baseband conversion, demodulation, demapping, depuncturing,decoding, and/or descrambling. The baseband processing module 88 may beimplemented using a processing device and may have associated memory.Such a processing device may be a microprocessor, micro-controller,digital signal processor, microcomputer, central processing unit, fieldprogrammable gate array, programmable logic device, state machine, logiccircuitry, analog circuitry, digital circuitry, and/or any device thatmanipulates signals (analog and/or digital) based on operationalinstructions. The associated memory may be a single memory device or aplurality of memory devices. Such a memory device may be a read-onlymemory, random access memory, volatile memory, non-volatile memory,static memory, dynamic memory, flash memory, and/or any device thatstores digital information. Note that when the baseband processingmodule 88 implements one or more of its functions via a state machine,analog circuitry, digital circuitry, and/or logic circuitry, theassociated memory storing the corresponding operational instructions isembedded with the circuitry comprising the state machine, analogcircuitry, digital circuitry, and/or logic circuitry.

In operation, the RFIC 80 receives inbound RF signals 92 via an antenna,which were transmitted by a base station, an access point, or anotherwireless communication device. The antenna provides the inbound RFsignals 92 to the low noise amplifier (LNA) 82, which amplifies thesignals 92 to produce an amplified inbound RF signals. The conversionmixing module 84 converts the amplified inbound RF signals into a downconverted signal 96, which may be an intermediate frequency or be atbaseband, based on a local oscillation module 94.

The analog-to-digital converter module 86 converts the down convertedsignal 96 from the analog domain to the digital domain to produce adigital signal 98. The baseband processing module 88 decodes,descrambles, demaps, de-framing, and/or demodulates the digital signal98 to recapture inbound data 100 in accordance with a particularwireless communication standard being implemented by the RFIC 80. Notethat an interpolating and/or anti-aliasing filter may be requiredbetween the ADC module 86 and the baseband processing module 88, wherethe interpolating and/or anti-aliasing filter is clocked at a rate basedon the operation dependent clock signal 104. Further note that eachfunction of the baseband processing module 88 may be clocked from thesame clock, different clocks, or a combination thereof. As such, theoperation dependent clock signal 104 may include one or more clocksignals.

In this embodiment, the clock module 90 generates a first clock signal102 and an operation dependent clock signal 104 such that the rate ofthe first clock signal 102 is set such that frequency dependent noisecomponents associated with the first clock signal 102 are outside afrequency band associated with the inbound RF signal 92 and the rate ofthe operation dependent clock signal 104 is set based on processingspecifications of the digital signal 98. The processing specificationsinclude rates for one or more of framing, demapping, deinterleave, IFFT,decoding, descramble, etc.

The ADC module 86 is clocked by the first clock signal 102 and generatesfrequency dependent noise that may be present in the RFIC 80. Thefrequency dependent noise, which may be harmonic signal components,spurs, and/or digital noise, may appear on the substrate of the IC 80,on the positive supply voltage rail, on negative supply voltage rail,and/or on a voltage return rail. The baseband processing module 88 isclocked by the operation dependent clock 104 to produce the inbound data100 from the digital signal 98. In this manner, the frequency dependentnoise components produced by the digital portion of the ADC module 86 donot adversely interfere with the LNA's 82 amplifying of the inbound RFsignal 92 and yet the baseband processing module 88 is clocked at a raterequired to recover the inbound data 100.

As one of ordinary skill in the art will appreciate, buffering may berequired between noisy circuits and operation rate dependent circuits tocompensate for the different clocking rates. Alternatively, the clockmodule and/or the rate adapting module may include a sample rateconverter to accommodate the differences in clocking rates.

FIG. 6 is a schematic block diagram of an embodiment of a downconversion module 84 that includes a local oscillation module 114, amixing module 110, and a filtering module 112. The mixing module 110includes a pair of mixers and a pair of 90° phase shift modules. Thefirst mixer mixes the amplified inbound RF signal 92 with the localoscillation 94 to produce a first mixed signal. The second mixer mixes a90° phase shifted version of the amplified inbound RF signal 92 with a90° phase shifted version of the local oscillation 94 to produce asecond mixed signal.

The filtering module 112 filters out higher frequency components of thefirst and second mixed signals to produce an in-phase component and aquadrature component of the down converted signal 96. Note that toprocess the in-phase component and a quadrature component of the downconverted signal 96, the ADC module 86 would include two ADCs; one foreach signal component. Alternatively, a single ADC can be clocked attwice the frequency and shared by the in-phase and quadrature phasesections.

FIG. 7 is a schematic block diagram of an embodiment of a clock module90 that includes a clock source 120 and a rate adjust module 122. Theclock source 120, which may be a fractional-N frequency synthesizer, adirect digital frequency synthesizer, a phase locked loop, generates thefirst clock signal 102.

The rate adjust module 122, which may be a fractional-N frequencysynthesizer, a direct digital frequency synthesizer, a phase lockedloop, and/or digital logic circuitry (e.g., a digital delay line toproduce a plurality of delayed clock signals from the clock signal 62, aplurality of inverters to produce a plurality of inverted delayed clocksignals, a multiplexer to select one of the plurality of delayed orinverted delayed clock signals to clock a D flip-flop), generates theoperation dependent clock 104 from the first clock signal 102.

In one embodiment, the clock source 120 determines whether components ofthe frequency dependent noise are within the given frequency range ofthe inbound RF signal. Note that the determining may be done bycalculating frequency of the components of the frequency dependent noisebased on an initial setting of the first clock signal 102 and the givenfrequency range. Alternatively, the RFIC 80 may be operated in a testmode at the initial rate of the first clock signal 102 and monitoringperformance of the LNA 82. If LNA 82 experiences minimal adverse affectsdue to the frequency dependent noise then it can be assumed that thereare no significant components of the frequency dependent noise in thegiven frequency range.

When the frequency dependent noise components are within the givenfrequency range, the clock source 120 adjusts the rate of the firstclock signal 102 such that the frequency dependent noise componentsassociated with the first clock signal 102 are outside the givenfrequency range. In one embodiment, the clock source 120 adjusts therate of the first clock signal 102 by calculation. For instance, if thegiven frequency range is from 960 MHz to 1040 MHz, and the initial rateof the first clock is 100 MHz, the tenth harmonic of the first clocksignal 102 is 1000 MHz and is within the given frequency range. As such,the clock source 120 determines that a clock rate of 105 MHz produces aninth harmonic at 945 MHz and a tenth harmonic at 1050 MHz, both ofwhich are outside of the given frequency range. Alternatively, the clocksource 120 may use a clock rate of 95 MHz, which has a tenth harmonic at950 MHz and an eleventh harmonic at 1045 MHz, both of which are outsidethe given frequency range.

In another embodiment, the clock source 120 may incrementally increaseor decrease the rate of the first clock signal 102 during a test mode,where the RFIC 80 monitors for adverse performance of the LNA 82 due tothe frequency dependent noise. When an acceptable level of performanceis obtained for a given rate of the first clock signal, it is used forthe first clock signal 102.

FIG. 8 is a schematic block diagram of another embodiment of a clockmodule 90 that includes the clock source 120 and a rate adjust module124. The clock source 120, which may be a fractional-N frequencysynthesizer, a direct digital frequency synthesizer, a phase lockedloop, generates the operation dependent clock signal 104.

The rate adjust module 124, which may be a fractional-N frequencysynthesizer, a direct digital frequency synthesizer, a phase lockedloop, and/or digital logic circuitry (e.g., a digital delay line toproduce a plurality of delayed clock signals from the clock signal 62, aplurality of inverters to produce a plurality of inverted delayed clocksignals, a multiplexer to select one of the plurality of delayed orinverted delayed clock signals to clock a D flip-flop), generates thefirst clock signal 102 from the operation dependent clock signal 104.

In one embodiment, the rate adjust module 124 establishes the firstclock signal 102 by establishing an adjustment factor based on the givenfrequency range and the operation dependent clock signal 104. Forexample, if the given frequency range is 960 MHz to 1040 MHz and therate of the operation dependent clock signal 104 is 100 MHz, then theoperation dependent clock signal has a tenth harmonic at 1000 MHz. Therate adjust module 124 may then determine the adjustment factor as960/1000 or 1040/1000. Having established the adjustment factor, therate adjust module 124 adjusts the rate of the operation dependent clocksignal 104 based on the adjustment factor to produce the first clocksignal 102.

In one embodiment, the rate adjust module 124 determines whethercomponents of the frequency dependent noise are within the givenfrequency range. Note that the determining may be done by calculatingfrequency of the components of the frequency dependent noise based onthe clock rate. Alternatively, the RFIC 80 may be operated in a testmode at the rate of the operation dependent clock signal 104 andmonitoring performance of the LNA 82. If LNA 82 experiences minimaladverse affects due to the frequency dependent noise then it can beassumed that there are no significant components of the frequencydependent noise in the given frequency range.

When the frequency dependent noise components are within the givenfrequency range, the rate adjust module 124 adjusts the rate of thefirst clock signal 102 such that the frequency dependent noisecomponents associated with the first clock signal 102 are outside thegiven frequency range. In one embodiment, the rate adjust module 124adjusts the rate of the operation dependent clock signal 104 bycalculation. For instance, if the given frequency range is from 960 MHzto 1040 MHz, and the rate of the operation dependent clock is 100 MHz,the tenth harmonic of the operation dependent clock signal 104 is 1000MHz and is within the given frequency range. As such, the rate adjustmodule 124 determines that a clock rate of 105 MHz produces a ninthharmonic at 945 MHz and a tenth harmonic at 1050 MHz, both of which areoutside of the given frequency range. Alternatively, the rate adjustmodule 124 may use a clock rate of 95 MHz, which has a tenth harmonic at950 MHz and an eleventh harmonic at 1045 MHz, both of which are outsidethe given frequency range.

In another embodiment, the rate adjust module 124 may incrementallyincrease or decrease the rate of the first clock signal 102 during atest mode, where the RFIC 80 monitors for adverse performance of the LNA82 due to the frequency dependent noise. When an acceptable level ofperformance is obtained for a given rate of the first clock signal, itis used for the first clock signal 102.

FIG. 9 is a schematic block diagram of an embodiment of a radiofrequency integrated circuit in accordance with the present invention.Clock module 90 generates a plurality of baseband clock signals 130 thatclock one or more functions of baseband processing module 88. Thebaseband clock signals are generated to reduce potential interferencegenerated by the harmonics, spurs or other frequency dependent noisecomponents of these clock signals falling within the passband of the RFfront end of RFIC 80, generally set to correspond to the frequency bandassociated with possible carrier frequencies of the inbound RF signal92. In one embodiment of the present invention, when frequency dependentnoise components of one or more of the clock signals 130 fall within afrequency band associated with the inbound RF signal 92, the clocksignals are either adjusted in frequency so that frequency dependentnoise components fall outside of this frequency band, or the spectrum ofthe clock signals are spread to place some of the signal energy from thefrequency dependent noise components outside of this frequency band.

In particular, RFIC 80 includes a low noise amplifier 82 that is coupledto amplify an inbound radio frequency (RF) signal 92 to produce anamplified RF signal. Down conversion module 84 is coupled to convert theamplified RF signal to a down converted signal 96 based on a localoscillation. Analog to digital conversion (ADC) module 86 is coupled toconvert the down converted signal into a digital signal 98. Basebandprocessing module 88 is coupled to convert the digital signal 98 intoinbound data 100. At least one function of the baseband processingmodule 88 is clocked by a plurality of baseband clock signals 130. Thepossible functions of baseband processing module 88 include intermediatefrequency to baseband conversion, fast Fourier transform, demapping,deinterleaving, decoding, descrambling and other signal processingfunctions that can be dependent on one or more clock signals for timingthereof.

In one embodiment, the clock module 90 is coupled to produce theplurality of baseband clock signals 130 such that the rate of each ofthe plurality of baseband clock signals is set such that frequencydependent noise components associated with each of the plurality ofbaseband clock signals 130 fall outside a frequency band associated withthe inbound RF signal 92. As will be discussed in greater detail inconjunction with FIGS. 12 and 13, the clock module 90 can optionallyoperate to reduce the effect of the frequency dependent noise componentsby spreading the spectrum of one or more of the baseband clock signals130.

In a similar fashion to the embodiments previously described, the ADCconversion module 86 can clocked by an ADC clock signal 132, such as the1^(st) clock signal 102. In this case, the clock module 90 produces theADC clock signal 132 at a rate such that frequency dependent noisecomponents associated with the ADC clock signal are outside thefrequency band associated with the inbound RF signal 92.

As discussed in conjunction with FIG. 6, the down conversion module 84can include a local oscillation module 114 that is coupled to generatethe local oscillation 94 based on the operation dependent clock signal,a mixing module 110 that is coupled to mix the local oscillation 94 withthe amplified RF signal to produce first and second mixed signals, and afiltering module 112 that is coupled to filter the first and secondmixed signals to produce an in-phase component and a quadraturecomponent of the down converted signal 96.

FIG. 10 is a schematic block diagram of an embodiment of a clock modulein accordance with the present invention. In particular, clock module 90includes a clock source 120 that generates an operation dependent clocksignal 104. In an embodiment of the present invention, the operationdependent clock signal has a frequency that varies based on the desiredchannel and/or carrier frequency of the inbound RF signal 92 that is tobe received. The local oscillation is generated based on this operationdependent clock signal 104 to down convert the inbound RF signal 92 aspreviously discussed. The plurality of rate adjust modules 124, in turn,generate the plurality of baseband clock signals from the operationdependent clock signal. In the parallel configuration shown, each of therate adjust modules are independent and can each adjust the frequency ofthe operation dependent clock signal 104 to form adjusted clock signals140, such as the baseband clock signals 130 and the ADC clock signal132, such that the frequency dependent noise components of theseadjusted clock signals 140 avoid the frequency range of the input thatis susceptible to noise. As previously discussed, each of these rateadjust modules 124 can be implemented using fractional-N frequencysynthesizers, direct digital frequency synthesizer, a phase locked loop,a frequency divider and/or other digital logic circuitry.

In one embodiment, the rate adjust module 124 produces its correspondingadjusted clock signal 140 by establishing an adjustment factor based onthe given frequency range and the operation dependent clock signal 104.For example, if the given frequency range is 960 MHz to 1040 MHz and therate of the operation dependent clock signal 104 is 100 MHz, then theoperation dependent clock signal has a tenth harmonic at 1000 MHz and aninterference condition is detected. The rate adjust module 124 may thendetermine the adjustment factor as 960/1000 or 1040/1000. Havingestablished the adjustment factor, the rate adjust module 124 adjuststhe rate of the operation dependent clock signal 104 based on theadjustment factor to produce the corresponding adjusted clock signal140.

In one embodiment, the rate adjust module 124 determines whethercomponents of the frequency dependent noise are within the givenfrequency range. Note that the determining may be done by calculatingfrequency of the components of the frequency dependent noise based onthe clock rate. Alternatively, the RFIC 80 may be operated in a testmode at the rate of the operation dependent clock signal 104 to monitorperformance of the LNA 82 to detect an interference condition based onone or more receiver parameters such as signal to noise ratio, signal tointerference ratio, bit error rate, noise power or other receiverparameter that either directly or indirectly indicates the presence orabsence of noise. If LNA 82 experiences minimal adverse affects due tothe frequency dependent noise then it can be assumed that there are nosignificant components of the frequency dependent noise in the givenfrequency range.

When the frequency dependent noise components are within the givenfrequency range, the rate adjust module 124 adjusts the rate of thefirst clock signal 102 such that the frequency dependent noisecomponents associated with the adjusted clock signal 140 are outside thegiven frequency range. In one embodiment, the rate adjust module 124adjusts the rate of the operation dependent clock signal 104 bycalculation. For instance, if the given frequency range is from 960 MHzto 1040 MHz, and the rate of the operation dependent clock is 100 MHz,the tenth harmonic of the operation dependent clock signal 104 is 1000MHz and is within the given frequency range. As such, the rate adjustmodule 124 determines that a clock rate of 105 MHz produces a ninthharmonic at 945 MHz and a tenth harmonic at 1050 MHz, both of which areoutside of the given frequency range. Alternatively, the rate adjustmodule 124 may use a clock rate of 95 MHz, which has a tenth harmonic at950 MHz and an eleventh harmonic at 1045 MHz, both of which are outsidethe given frequency range.

In another embodiment, the rate adjust module 124 may incrementallyincrease or decrease the rate of the adjusted clock signal 140 during atest mode, where the RFIC 80 monitors for adverse performance of the LNA82 due to the frequency dependent noise. When an acceptable level ofperformance is obtained for a given rate of the first clock signal, itis used for the adjusted clock signal 140.

FIG. 11 is a schematic block diagram of another embodiment of a clockmodule in accordance with the present invention. In this embodiment, therate adjust modules 124 are arranged serially, rather than the parallelconfiguration of FIG. 10. This embodiment is well suited forimplementations where two or more of the adjusted clock signals 140 aredependent upon one another, such as by a fixed relationship. Forinstance, where one of the adjusted clock signals is, say four timesgreater than another, one of the rate adjust modules 124 can include adivide-by-four circuit. In this embodiment, one of the rate adjustmodules can take responsibility to avoid interference caused byfrequency dependent noise components for more than one of the adjustedclock signals 140 and make adjustments that allow one or more of theother rate adjust modules 124 to remain at a fixed relationship betweenits input and output.

FIG. 12 is a schematic block diagram of an embodiment of a clock sourcein accordance with the present invention. In particular, a clock source120 is shown that has a clock source 121 that can include an oscillatorsuch as a ring-oscillator, crystal oscillator or other oscillatorcircuit, phase locked loop circuit, or other circuit that generates aclock signal 127. This clock signal is adjusted by rate adjust modules124′ that adjust the clock signal 127 to a plurality of different rates.Demultiplexer 123 selects a particular one of the plurality of clocksignals to have a rate of the plurality of rates that, when adjusted byrate adjustment modules 124 of the clock module 90, avoids the unwantedinterference. It should be noted in this embodiment, that the rateadjustment modules 124′ and 124 can be implemented as predetermined orfixed rate adjustments with the frequency of clock signal 125 and of theadjusted clock signals 140, instead, varying based on a selection of aparticular clock signal by demultiplexer 123.

For example, clock source 121 can generate a 26 MHz clock signal 127that is adjusted by a first rate adjustment module 124′ that multipliesthe frequency by a factor of 24, to a 624 MHz clock, and by a secondrate adjust module 124′, that divides by 4 and multiplies by 95 to forma 617.5 MHz clock signal. Demultiplexer selects either the 624 MHz clockor the 617.5 MHz clock under control of a processor of RFIC 80 based onthe particular band or channel that is being received, based oninterference measurements, etc. In this example, rate adjust modules 124of clock module 90 can include fixed dividers to generate the rateadjusted clock signals 140, such as baseband clock signals 130.

FIG. 13 is a schematic block diagram of another embodiment of a clocksource in accordance with the present invention. In this embodimentclock source 120′ includes a plurality of separate clock sources, suchas clock source 121 that generates clock signal 127 and clock source 123that generates clock signal 127′. As in the circuit of FIG. 12,demultiplexer 123 selects a particular clock signal 125 from theplurality of clock signals 127, 127′, . . . to avoid potentially harmfulinterference.

FIG. 14 is a schematic block diagram of another embodiment of a clockmodule in accordance with the present invention. In this embodiment ofthe present invention, the clock module 90 operates to reduce the effectof the frequency dependent noise components by spreading the spectrum ofone or more of the baseband clock signals 130. In particular, clockmodule 90 produces the plurality of adjusted clock signals 150, such asbaseband clock signals 130. Clock module 90 includes a clock source 120that generates an operation dependent clock signal 148. A plurality ofspectrum adjust modules 144, optionally arranged in a parallelconfiguration, generate the plurality of adjusted clock signals 150 fromthe operation dependent clock signal 148. In operation, each of thespectrum adjust modules 144 detect an interference condition in a mannersimilar to rate adjust modules 122, 124, etc., either by test orcalculation, when frequency dependent noise components associated thecorresponding adjusted clock signals 150 are inside a frequency bandassociated with the inbound RF signal 92. In response, the spectrumadjust module 144 spreads the spectrum of its corresponding adjustedclock signal 150 when the interference condition is detected. In anembodiment of the present invention, each of the spectrum adjust modulesincludes a programmable delay line, tapped delay line, or other circuitfor introducing jitter, that is either periodic, non-periodic,pseudorandom, etc. on the operation dependent clock signal 148 or thatotherwise spreads the spectrum of operation dependent clock signal 148to produce the corresponding adjusted clock signal 150. This spectrumadjust module 144 can include analog and/or digital circuits that can beimplemented on an integrated circuit that may include a processingelement such as a dedicated processor or shared processing functionincluding, but not limited to a programmable logic array, digital signalprocessor, microprocessor, state machine, or other processing element.

In an embodiment of the present invention, the adjusted clock signals150 further include an ADC clock signal 132 that is generated at a ratesuch that frequency dependent noise components associated with the ADCclock signal are outside the frequency band associated with the inboundRF signal. In an alternative embodiment, ADC clock signal 132 isgenerated by clock module 120 in a manner similar to the generation ofthe baseband clock signals 130. in particular, clock module 120 detectsthe interference condition when frequency dependent noise componentsassociated with the ADC clock signal 132 are inside a frequency bandassociated with the inbound RF signal 92, and that spreads the spectrumof the ADC clock signal 132 when the interference condition is detected.

FIG. 16 is a frequency diagram of clock spectrum adjusting in accordancewith the present invention. In particular, a clock signal, such asoperation dependent clock signal 148, is shown to have a fundamentalfrequency 200 and a plurality of harmonics 202. As shown one of theharmonics falls within a given frequency range, such as the passband ofLNA 82, providing a potential source of noise. In response to thedetection of the condition, clock module 90, such as through operationof spectrum adjust module 144, operates to introduce jitter to the clocksignal to spread the spectrum of the fundamental 200 and each of theharmonic components 202 to produce the spectral components 200′ and202′. As shown, this reduces the energy of this frequency dependentnoise that falls within the given frequency range 40 and lowers themagnitude of the noise at any particular frequency within the givenfrequency range 40, helping to reduce the impact of this source ofnoise.

FIG. 16 is a flow chart of a method in accordance with the presentinvention. In particular, a method is presented for use with one or moreof the functions or features presented in conjunction with FIGS. 1-15.In step 400, an inbound is amplified to produce an amplified RF signal.In step 404, the amplified RF signal is converted to a down convertedsignal based on a local oscillation. In step 408, the down convertedsignal is converted into a digital signal. In step 412, a plurality ofbaseband clock signals are generated, wherein a rate of each of theplurality of baseband clock signals is set such that frequency dependentnoise components associated with each of the plurality of baseband clocksignals are outside a frequency band associated with the inbound RFsignal. In step 416, the digital signal is converted into inbound databased on at least one function that is clocked by the plurality ofbaseband clock signals.

In an embodiment of the present invention, step 412 includes generatingan operation dependent clock signal, and adjusting the operationdependent clock signal to produce the plurality of baseband clocksignals. In addition, the at least one function that is clocked by theplurality of baseband clock signals can include one or more of thefollowing: intermediate frequency to baseband conversion; fast Fouriertransform; demapping; deinterleaving; decoding; and descrambling.

FIG. 17 is a flow chart of a method in accordance with the presentinvention. In particular a method is presented that includes manyelements of FIG. 16 that are referred to by common reference numerals.Like the method of FIG. 16, this method can be used in conjunction withone or more features or functions described in conjunction with FIGS.1-15. In addition, this method includes step 406 of generating an analogto digital conversion (ADC) clock signal at a rate such that frequencydependent noise components associated with the ADC clock signal areoutside the frequency band associated with the inbound RF signal, andstep 408 is performed based on the ADC clock signal that is generated.Further the method includes step 402 of generating the local oscillationbased on an operation dependent clock signal. In an embodiment of thepresent invention, step 404 further includes mixing the localoscillation with the amplified RF signal to produce first and secondmixed signals, and filtering the first and second mixed signals toproduce an in-phase component and a quadrature component of the downconverted signal.

FIG. 18 is a flow chart of a method in accordance with the presentinvention. In particular a method is presented that includes many ofcommon elements of the method of FIG. 16 that are referred to by commonreference numerals. Like the method of FIG. 16, this method can be usedin conjunction with one or more features or functions described inconjunction with FIGS. 1-15. In addition, the method includes step 414of generating a plurality of baseband clock signals, by detecting aninterference condition when frequency dependent noise componentsassociated with at least one of the plurality of baseband clock signalsare inside a frequency band associated with the inbound RF signal, andspreading the spectrum of the at least one of the plurality of basebandclock signals when the interference condition is detected.

In an embodiment of the present invention, step 414 includes generatingan operation dependent clock signal, and spreading the spectrum of theoperation dependent clock signal to produce the plurality of basebandclock signals. In addition, the at least one function that is clocked bythe plurality of baseband clock signals can includes at least one of:intermediate frequency to baseband conversion; fast Fourier transform;demapping; deinterleaving; decoding; and descrambling.

FIG. 19 is a flow chart of a method in accordance with the presentinvention. In particular a method is presented that includes many ofcommon elements of the method of FIG. 17 that are referred to by commonreference numerals. Like the method of FIG. 17, this method can be usedin conjunction with one or more features or functions described inconjunction with FIGS. 1-15. In addition this method includes step 406of generating an analog to digital conversion (ADC) clock signal at arate such that frequency dependent noise components associated with theADC clock signal are outside the frequency band associated with theinbound RF signal.

FIG. 20 is a flow chart of a method in accordance with the presentinvention. In particular a method is presented that includes many ofcommon elements of the method of FIG. 17 that are referred to by commonreference numerals. Like the method of FIG. 17, this method can be usedin conjunction with one or more features or functions described inconjunction with FIGS. 1-15. In addition, this method includes step 407of generating an analog to digital conversion (ADC) clock signal,detecting the interference condition when frequency dependent noisecomponents associated with the ADC clock signal are inside a frequencyband associated with the inbound RF signal, and spreading the spectrumof the ADC clock signal when the interference condition is detected;

FIG. 21 is a flow chart of a method in accordance with the presentinvention. This method can be used in conjunction with one or morefeatures or functions described in conjunction with FIGS. 1-20. In step500 an interference condition is detected when frequency dependent noisecomponents associated with at least one of the plurality of basebandclock signals are inside a frequency band associated with an inbound RFsignal. In step 502, the spectrum of the at least one of the pluralityof baseband clock signals when the interference condition is detected.

As may be used herein, the terms “substantially” and “approximately”provides an industry-accepted tolerance for its corresponding termand/or relativity between items. Such an industry-accepted toleranceranges from less than one percent to fifty percent and corresponds to,but is not limited to, component values, integrated circuit processvariations, temperature variations, rise and fall times, and/or thermalnoise. Such relativity between items ranges from a difference of a fewpercent to magnitude differences. As may also be used herein, theterm(s) “coupled to” and/or “coupling” and/or includes direct couplingbetween items and/or indirect coupling between items via an interveningitem (e.g., an item includes, but is not limited to, a component, anelement, a circuit, and/or a module) where, for indirect coupling, theintervening item does not modify the information of a signal but mayadjust its current level, voltage level, and/or power level. As mayfurther be used herein, inferred coupling (i.e., where one element iscoupled to another element by inference) includes direct and indirectcoupling between two items in the same manner as “coupled to”. As mayeven further be used herein, the term “operable to” indicates that anitem includes one or more of power connections, input(s), output(s),etc., to perform one or more its corresponding functions and may furtherinclude inferred coupling to one or more other items. As may stillfurther be used herein, the term “associated with”, includes directand/or indirect coupling of separate items and/or one item beingembedded within another item. As may be used herein, the term “comparesfavorably”, indicates that a comparison between two or more items,signals, etc., provides a desired relationship. For example, when thedesired relationship is that signal 1 has a greater magnitude thansignal 2, a favorable comparison may be achieved when the magnitude ofsignal 1 is greater than that of signal 2 or when the magnitude ofsignal 2 is less than that of signal 1.

The present invention has also been described above with the aid ofmethod steps illustrating the performance of specified functions andrelationships thereof. The boundaries and sequence of these functionalbuilding blocks and method steps have been arbitrarily defined hereinfor convenience of description. Alternate boundaries and sequences canbe defined so long as the specified functions and relationships areappropriately performed. Any such alternate boundaries or sequences arethus within the scope and spirit of the claimed invention.

The present invention has been described above with the aid offunctional building blocks illustrating the performance of certainsignificant functions. The boundaries of these functional buildingblocks have been arbitrarily defined for convenience of description.Alternate boundaries could be defined as long as the certain significantfunctions are appropriately performed. Similarly, flow diagram blocksmay also have been arbitrarily defined herein to illustrate certainsignificant functionality. To the extent used, the flow diagram blockboundaries and sequence could have been defined otherwise and stillperform the certain significant functionality. Such alternatedefinitions of both functional building blocks and flow diagram blocksand sequences are thus within the scope and spirit of the claimedinvention. One of average skill in the art will also recognize that thefunctional building blocks, and other illustrative blocks, modules andcomponents herein, can be implemented as illustrated or by discretecomponents, application specific integrated circuits, processorsexecuting appropriate software and the like or any combination thereof.

1. A radio frequency integrated circuit (RFIC) comprising: a low noiseamplifier coupled to amplify an inbound radio frequency (RF) signal toproduce an amplified RF signal; a down conversion module coupled toconvert the amplified RF signal to a down converted signal based on alocal oscillation; an analog to digital conversion (ADC) module coupledto convert the down converted signal into a digital signal; a basebandprocessing module coupled to convert the digital signal into inbounddata, wherein at least one function of the baseband processing module isclocked by a plurality of baseband clock signals wherein the at leastone function of the baseband processing module includes at least one ofintermediate frequency to baseband conversion, fast Fourier transform,demapping, deinterleaving, decoding, and descrambling; and a clockmodule coupled to produce the plurality of baseband clock signals,wherein the clock module detects an interference condition whenfrequency dependent noise components associated with at least one of theplurality of baseband clock signals are inside a frequency bandassociated with the inbound RF signal, and that spreads the spectrum ofthe at least one of the plurality of baseband clock signals when theinterference condition is detected.
 2. The RFIC of claim 1 wherein theADC conversion module is clocked by an ADC clock signal and wherein theclock module produces the ADC clock signal at a rate such that frequencydependent noise components associated with the ADC clock signal areoutside the frequency band associated with the inbound RF signal.
 3. TheRFIC of claim 1 wherein the ADC conversion module is clocked by an ADCclock signal and wherein the clock module detects the interferencecondition when frequency dependent noise components associated with theADC clock signal are inside a frequency band associated with the inboundRF signal, and that spreads the spectrum of the ADC clock signal whenthe interference condition is detected.
 4. The RFIC of claim 1, whereinthe clock module comprises: a clock source that generates an operationdependent clock signal; and a plurality of spectrum adjust modules, thatgenerate the plurality of baseband clock signals from the operationdependent clock signal.
 5. The RFIC of claim 4 wherein the plurality ofspectrum adjust modules are arranged in a parallel configuration.
 6. TheRFIC of claim 3, wherein the down conversion module comprises: a localoscillation module coupled to generate the local oscillation based onthe operation dependent clock signal;
 7. The RFIC of claim 6, whereinthe down conversion module further comprises: a mixing module coupled tomix the local oscillation with the amplified RF signal to produce firstand second mixed signals; and a filtering module coupled to filter thefirst and second mixed signals to produce an in-phase component and aquadrature component of the down converted signal.
 8. A radio frequencyintegrated circuit (RFIC) comprising: a low noise amplifier coupled toamplify an inbound radio frequency (RF) signal to produce an amplifiedRF signal; a down conversion module coupled to convert the amplified RFsignal to a down converted signal based on a local oscillation; ananalog to digital conversion (ADC) module coupled to convert the downconverted signal into a digital signal; a baseband processing modulecoupled to convert the digital signal into inbound data, wherein atleast one function of the baseband processing module is clocked by aplurality of baseband clock signals; and a clock module coupled toproduce the plurality of baseband clock signals, wherein the clockmodule detects an interference condition when frequency dependent noisecomponents associated with at least one of the plurality of basebandclock signals are inside a frequency band associated with the inbound RFsignal, and that spreads the spectrum of the at least one of theplurality of baseband clock signals when the interference condition isdetected.
 9. The RFIC of claim 8 wherein the ADC conversion module isclocked by an ADC clock signal and wherein the clock module produces theADC clock signal at a rate such that frequency dependent noisecomponents associated with the ADC clock signal are outside thefrequency band associated with the inbound RF signal.
 10. The RFIC ofclaim 8 wherein the ADC conversion module is clocked by an ADC clocksignal and wherein the clock module detects the interference conditionwhen frequency dependent noise components associated with the ADC clocksignal are inside a frequency band associated with the inbound RFsignal, and that spreads the spectrum of the ADC clock signal when theinterference condition is detected.
 11. The RFIC of claim 8, wherein theclock module comprises: a clock source that generates an operationdependent clock signal; and a plurality of spectrum adjust modules, thatgenerate the plurality of baseband clock signals from the operationdependent clock signal.
 12. The RFIC of claim 11 wherein the pluralityof spectrum adjust modules are arranged in a parallel configuration. 13.The RFIC of claim 8, wherein the down conversion module comprises: alocal oscillation module coupled to generate the local oscillation basedon the operation dependent clock signal;
 14. The RFIC of claim 13,wherein the down conversion module further comprises: a mixing modulecoupled to mix the local oscillation with the amplified RF signal toproduce first and second mixed signals; and a filtering module coupledto filter the first and second mixed signals to produce an in-phasecomponent and a quadrature component of the down converted signal. 15.The RFIC of claim 8, wherein the baseband processing module is operableto perform at least one of: intermediate frequency to basebandconversion; fast Fourier transform; demapping; deinterleaving; decoding;and descrambling.
 16. A method comprising: amplifying an inbound radiofrequency (RF) signal to produce an amplified RF signal; converting theamplified RF signal to a down converted signal based on a localoscillation; converting the down converted signal into a digital signal;generating a plurality of baseband clock signals, by detecting aninterference condition when frequency dependent noise componentsassociated with at least one of the plurality of baseband clock signalsare inside a frequency band associated with the inbound RF signal, andspreading the spectrum of the at least one of the plurality of basebandclock signals when the interference condition is detected; andconverting the digital signal into inbound data based on at least onefunction that is clocked by the plurality of baseband clock signals. 17.The method of claim 16 further comprising generating an analog todigital conversion (ADC) clock signal at a rate such that frequencydependent noise components associated with the ADC clock signal areoutside the frequency band associated with the inbound RF signal;wherein the step of converting the down converted signal into a digitalsignal is performed based on the ADC clock signal.
 18. The method ofclaim 16 further comprising generating an analog to digital conversion(ADC) clock signal; detecting the interference condition when frequencydependent noise components associated with the ADC clock signal areinside a frequency band associated with the inbound RF signal; andspreading the spectrum of the ADC clock signal when the interferencecondition is detected; wherein the step of converting the down convertedsignal into a digital signal is performed based on the ADC clock signal.19. The method of claim 16, wherein the step of generating the pluralityof baseband clock signals includes generating an operation dependentclock signal, and spreading the spectrum of the operation dependentclock signal to produce the plurality of baseband clock signals.
 20. Themethod of claim 18, further comprising: generating the local oscillationbased on an operation dependent clock signal.
 21. The method of claim19, wherein the step of converting the amplified RF signal to a downconverted signal further comprises: mixing the local oscillation withthe amplified RF signal to produce first and second mixed signals; andfiltering the first and second mixed signals to produce an in-phasecomponent and a quadrature component of the down converted signal. 22.The method of claim 16, wherein the at least one function that isclocked by the plurality of baseband clock signals includes at least oneof: intermediate frequency to baseband conversion; fast Fouriertransform; demapping; deinterleaving; decoding; and descrambling.
 23. Amethod for generating a plurality of baseband clock signals, the methodcomprising: detecting an interference condition when frequency dependentnoise components associated with at least one of the plurality ofbaseband clock signals are inside a frequency band associated with aninbound RF signal; and spreading the spectrum of the at least one of theplurality of baseband clock signals when the interference condition isdetected.